What will be the main energy source in 2050?

Currently, fossil fuels (coal, oil, and natural gas) are dominant energy sources for electricity generation in the world. However, many claim that renewable energy will be the main form of energy in the future. The circle graph below shows one prediction of shares of energy sources used for electricity generation in the world in 2050.

According to the prediction, what two sources will be the dominant energy sources in the world in 2050?

According to the prediction, what percentages of the world’s energy will be generated from fossil fuels in 2050? Fossil fuels include coal, oil, and natural gas.

According to the prediction, what energy source generates one-sixth as much electricity as solar energy in the world in 2050?

According to the prediction, what energy source generates 4 times as much electricity as coal in the world in 2050?